The use of ceramic-based materials, such as SiC—SiC and C—C based ceramic matrix composites (CMC) in the hot sections of gas turbine engines has emerged as an alternative to super alloy-based engine components. However, this has prompted the need for a high-resolution surface temperature measurement (STS) as well as a local thermal gradient measurement (TGS). The present invention relates to the use of a device that can be applied to the surface of CMCs in such a way that the CMC itself will contribute to the extraordinarily large thermoelectric power.